ARCHIVED REPORTS_ANNUAL 2010 GROUNDWATER MONITORING AND SAMPLING REPORT

Home Browse Search

' Mr.Lee Higgins—CEMC Annual 2010 Groundwater Monitoring and Sampling Report April 19,2010 Alden Park ' Page 5 of 7 GROUNDWATER ANALYTICAL RESULTS Groundwater samples collected on January 5 and 6, 2010, from MW-4, MW-7 through MW-12, and MW-14 were analyzed for the following constituents: • TPHd(C1d—C25), using U.S. Environmental Protection Agency (EPA) Method ' 8015B; and • PAHs using EPA Method 8270C with large-volume injection. ' The groundwater analytical results are summarized and compared with the numerical State Water Quality Objectives (WQOs) and the RWQCB Region 2 Environmental Screening Levels (ESLs) in Tables 2 and 3.4 Analytical results exceeding the most tconservative ESL and/or WQO are highlighted in Tables 2 and 3 in bold font. TPHd were present above the WQO and ESL in MW-7, which is consistent with previous sampling events. The PAHs benzo(a)pyrene, benzo(b)fluoranthene, ' benzo(k)fluoranthene, dibenz(a,h)anthracene, and indeno(1,2,3-cd)pyrene were detected in MW-8 in concentrations that exceeded the respective WQOs and/or ESLs. A copy of the laboratory analytical report and the data usability summary are provided as 1 Attachment C. See Attachment C for details regarding data qualifiers. QUARTERLY SPO EXTRACTION AND PRODUCT-THICKNESS MEASUREMENTS Vacuum extraction of SPO was performed quarterly throughout 2009 (April 22, July 16, and November 24, 2009) and during the first quarter of 2010 (January 7, 2010). Approximately 122.3 gallons of SPO were removed from wells MW-1, MW-3,MW-5, MW-6, MW-15, MW-16, MW-18, MW-20, and MW-21 during 2009; and a total of ' 40.07 gallons were removed during the first quarter of 2010. Approximately 926.80 gallons of SPO have been removed from the wells to date. SPO thickness ranged from 5.89 feet in MW-1 to 10.30 feet in MW-6 during the first quarter 2010 event. Oleophilic socks are currently in wells MW-5 and MW-21. See Table 4 for a summary of SPO thickness measured and cumulative volumes extracted. Copies of the field data sheets containing SPO measurements are included as Attachment 1 B. OLEOPHILIC SOCK REPLACEMENT 1 Oleophilic socks were installed in MW-5 and MW-21 in 2004 due to the presence of relatively low amounts of SPO. The socks were removed and inspected on January 7, 2010. Approximately 0.06 gallon of SPO was recovered from MW-5, and a replacement ' sock was installed. No measurable SPO was recovered from MW-21, and the sock was re-installed. 1 4. The WQOs are defined b the Porter-Cologne Act " Y g as the levels or limits of water quality constituents or characteristics which are established for the reasonable protection of beneficial uses of water or the prevention of ' nuisance within a specific area." The ESLs(provided as a reference)are a tool based on conservative standard exposure factors for initial human health and the environment screening-level evaluations of analytical results.